High yield manufacture is called for in the manufacture of electronic components, such as semiconductor devices, e.g., semiconductor memories like dynamic random-access memories, microprocessors and semiconductor lasers, and magnetic heads. This is because a fall of product yield leads to lower profits. Therefore, early detection of and measures needed to deal with defects, foreign matter and poor machining are major issues. For example, in electronic component manufacturing plants, much effort is expended on discovery of defects by careful inspection, and analysis of their cause. In actual electronic component manufacturing processes using wafers, the wafers in the course of being processed are examined, the cause of abnormalities such as defects and foreign matter in circuit patterns is investigated, and methods to deal with them are considered.
Usually, a scanning electron microscope (SEM: Scanning Electron Microscope, hereafter SEM) of super-resolution capacity is used for observation of sample abnormalities. In recent years, composite FIB-SEM devices which combine SEM and FIB (Focused Ion Beams) have also come to be used. With this FIB-SEM device, SEM observation of a cross-section can be performed by irradiating a FIB and forming rectangular holes in a desired part.
In JP-A No. 150990/2002, “Micro Sample Machining Observation Method and Device”, a device which observes and analyzes defects and foreign matter by forming rectangular holes near the abnormal spot of a sample by FIB, and observes the cross-section of these rectangular holes by a SEM device, is disclosed.
In international publication WO99/05506, “Sample Manufacturing Method and Device”, a technique of extracting a micro sample for TEM observation from a bulk sample by using FIB and a probe, is disclosed.
In JP-A No. 156393/2000, “Electronic Component Manufacturing Method”, a technique for removing a micro sample for inspection from a wafer without splitting the wafer, and returning the wafer after taking out the micro sample to the production line, is disclosed. In the invention disclosed in this document, the progress of the machining process is monitored by a monitor, and the wafer is inspected and analyzed.
In JP-A No. 320670/1995, “Processing Method and Device Using a Focused Ion Beam”, a technique using a helicon wave ion source for machining a sample for SEM observation by an argon ion beam with a beam spot diameter of 0.1 μm, is disclosed.    [Patent document 1] JP-A No. 150990/2002    [Patent document 2] International publication WO99/05506    [Patent document 3] JP-A No. 156393/2000    [Patent document 4] JP-A 320670/1995